WO2020030559A1

WO2020030559A1 - Device for spreading granulate

Info

Publication number: WO2020030559A1
Application number: PCT/EP2019/070955
Authority: WO
Inventors: Alexander Reich; Werner Bartling; Ralf Weiss
Original assignee: Nowe Gmbh
Priority date: 2018-08-06
Filing date: 2019-08-05
Publication date: 2020-02-13
Also published as: PL3768563T3; CA3102482A1; AT521564B1; CA3102482C; EP3768563A1; US20210146966A1; CN112512892A; EP3768563B1; ES2883777T3; RU2753376C1; AT521564A1

Abstract

The invention relates to a device (1) for spreading granulate (2), in particular for spreading sand into the gap between rail (3) and wheel (4) of a rail vehicle (5), having a housing (6), having at least one inlet (7) for the granulate (2), and having at least one outlet (8) for the granulate (2), having an axially movable dosing piston (9), and having a compressed-air connection (11) which opens out in a pressure chamber (10) and which serves for the actuation of the dosing piston (9) by means of compressed air for the purposes of dosing the granulate (2), wherein at least one bore (14) is provided in the dosing piston (9). To create a device (1) which is of particularly simple and compact construction, a conveying air chamber (12) which is separate from the pressure chamber (10) and which has a compressed-air connection (13) is provided, and the at least one bore (14) in the dosing piston (9) connects the conveying air chamber (12) to the at least one outlet (8) for the granulate (2), such that the granulate (2) can be conveyed to the at least one outlet (8) independently of the dosing by means of compressed air.

Description

Device for spreading granules

The invention relates to a device for spreading granu lat, in particular for spreading sand into the gap between the rail and wheel of a rail vehicle, with a housing, at least one inlet for the granulate and at least one outlet for the granulate, an axially movable metering piston and a compressed air connection opening into a pressure chamber for actuating the metering piston by means of compressed air for metering the granulate, at least one bore being provided in the metering piston.

Particularly in the case of rail vehicles, it is customary to spread the static friction between the vehicle wheel and the rail head for starting or braking by scattering granules, in particular sand, into the gap between the rail and the rail wheel. For this purpose, such spreading devices are arranged in front of the wheels of the rail vehicle and controlled via the vehicle control, for example manually or also automatically. It is necessary to dose a suitable amount of granules from a container provided for this purpose and via a corresponding delivery line to Transport gap between rail and wheel.

Conventional devices for spreading granules therefore usually comprise a corresponding metering device and a discharge device separate therefrom. In addition to electrically, electromagnetically or pneumatically operated pistons, rotating cell wheels are also suitable for dosing a desired amount of granules.

The metered granulate is usually conveyed via a conveyor line to the gap between the rail and the wheel if it is carried out using compressed air, as described, for example, in AT 403 559 B.

Another scattering device operated via compressed air has become known, for example, from WO 2008/061650 A1.

FR 593 382 A describes a device for spreading granules of the type in question, the metering and conveying Change or loosening of the granules at the beginning of the conveyor line with one and the same compressed air flow.

EP 656 292 A1 discloses a sand spreading device in which pneumatic metering and conveying of the sand takes place in a very complex manner.

The metering and conveying devices of known devices for spreading granules are often relatively large, which is why the like constructions are little for retrofitting existing ones

Rail vehicles with a limited space are suitable. In addition, a relatively high energy input or a high compressed air requirement is required for the transport of the metered granules over larger spatial distances.

The object of the invention is to provide an above-mentioned device for spreading granules, which has a compact and space-saving structure, so that after armor is possible even with existing rail vehicles with limited space. The scattering device in question is also to be distinguished by particularly high efficiency with regard to the required energy requirement. Disadvantages known ter scattering devices should be avoided or at least reduced.

The object of the invention is achieved in that a conveying air chamber with a compressed air connection is provided which is separate from the pressure chamber, and in that the at least one bore in the metering piston connects the conveying air chamber with the at least one outlet for the granulate, so that the granulate by means of compressed air is independent of the Dosage to which at least one outlet can be conveyed. According to the invention, a spatial and functional integration of the metering and conveying function is achieved by the arrangement of a conveying air chamber which is separate from the pressure chamber and the at least one bore in the metering piston. In contrast to the state of the art, no separate device, for example a separate injector, is required to convey the metered granules, but the compressed air flow for conveying the granules to the outlet of the spreading device is via the conveying air chamber which is located behind the metering piston. takes place through which at least one bore is passed in the metering piston. The discharge of the conveying air at the front end of the metering piston takes place spatially separated from the inlet for the granulate, but in the immediate vicinity, so that the granulate and conveying air are optimally mixed. This contributes to the particularly efficient conveying of the granulate to the desired location, usually the gap between the rail and the wheel, with minimal use of energy. Essentially, the spreading device lying ahead is characterized by a piston metering without an injector. The structure of the spreading device is particularly space-saving and compact, which is why it is particularly suitable for retrofitting to rail vehicles with little available space. The compact and relatively simple structure of the spreading device also results in a reduced maintenance effort.

According to a feature of the invention, a plurality of preferably annular bores are arranged in the metering piston. This improves the distribution of the conveying air and leads to a uniform flow and consequently to a larger bridging conveying path or a lower energy expenditure and compressed air requirement.

If the bores are inclined to the central axis of the metering piston, a better conveyance of the granulate and a higher acceleration can be achieved. Tilt angles in the range between 1 ° and 5 ° have been found to be particularly suitable.

If a preferably annular granule chamber connected to the at least one inlet for the granules is arranged around that end of the metering piston which faces the at least one outlet for the granules, an improved continuous feed of the granules can be ensured. Due to the essentially annular inflow of the granulate and the preferably annular outflow of compressed air for conveying the granulate, the energy consumption for conveying the granulate and the compressed air requirement can be reduced further, or the granulate can be transported over long distances to the desired location. The at least one inlet for the granules is ideally inclined, preferably inclined by 30 ° to 60 °, in particular inclined by 45 °. With such an inclination of the granulate feed, a regular and continuous inflow of the granulate can be achieved.

If the end of the metering piston, which faces the at least one outlet for the granules, is pointed, better metering of the granules can be achieved, since the gap size can be varied continuously by moving the metering piston through the tip of the end of the metering piston.

According to a further feature of the invention, a spring is provided for resetting the metering piston. As a result, the dosing piston can be reset to the starting position without the use of compressed air. A helical spring, which has a predefined proportional spring characteristic, serves as the return spring. Alternatively, Tel lerfederpaket with comparable characteristics are also conceivable. In any case, the force of the return spring must bring about a quick and precise return of the dosing piston. In addition, the return spring prevents any unwanted leakage of the granules in the event of a drop in pressure.

The spring is preferably net angeord in a dense spring space. The arrangement of such a pressure-tight spring chamber, in which the return spring is arranged, forms a pressure cushion which facilitates the return of the metering piston.

If a valve is arranged in this spring chamber, the metering piston can be reset in a controlled manner.

The separation between the pressure chamber and the conveying air chamber can be formed by a separating element with a guide for the metering piston. The guide between the separating element and the metering piston can be formed, for example, by appropriate sealing lips.

Between the conveying air chamber and the at least one inlet for the Granules can be arranged to bypass a portion of the compressed air used to convey the granules to feed the granules. By managing part of the

Compressed air used by such a bypass can suppress Un suppress in the inlet for the granules, which could lead to a compression of the granules and consequently to a blockage of the promotion of the granules. Even a slight, brief overpressure in the feed of the granulate can prevent the occurrence of an undesirable negative pressure and thus incorrect dosages or incorrect conveying.

In order to be able to adjust the compressed air flowing in the bypass, a regulating screw is preferably provided in the bypass. In the simplest case, the regulating screw for setting the compressed air flowing through the bypass is formed by a regulating screw which changes the cross section of the bypass accordingly.

A seal, preferably an O-ring, can be arranged between the metering piston and the housing. Such a seal, which is preferably made of elastic material, e.g. If rubber is formed, it can be ensured that no granules get into the outlet of the spreading device in the idle state.

The at least one outlet for the granules can be connected to a conveying line. The over a corresponding flange or the like. The metered granulate transports attachable to the outlet to the intended location, in particular the gap between the wheel and rail of the rail vehicle, in order to increase the static friction between the wheel and rail and to facilitate starting or braking the rail vehicle.

According to one embodiment variant, the metering piston is essentially arranged horizontally and the housing can be connected to a container for the granulate from below. This variant is particularly suitable for retrofitting the spreading device for existing vehicles, in particular rail vehicles, since the overall height is particularly low. In this case, the spreading device can be easily connected and attached to an existing granulate container from below. Alternatively, the metering piston can also be substantially vertical and the housing can be arranged in a container for the granulate. This variant is more suitable for one

New construction of a rail vehicle, in which there is at most a larger space for accommodating the granulate container and the metering piston.

According to a variant of the invention, the compressed air connections are connected to a common compressed air line with the interposition of a throttle valve. Here, the dosing and conveying device of the Streuvor device in question is supplied via a common compressed air line or a common compressed air connection. This so-called single-line system is particularly suitable for a working pressure of 3 bar to 8 bar max. 10 bar, and is particularly suitable for bridging shorter conveying paths, e.g. below 1.5 m. Via the throttle valve or a flow resistance, the pressure for conveying the granules can be reduced accordingly compared to the pressure for the movement of the metering piston.

If a check valve is arranged in the compressed air line, a so-called after-blowing effect or a post-blowing function for blowing out the delivery line after completion of a spreading operation can be achieved or improved. After switching off the compressed air supply, the dosing piston is moved back to its starting position. The remaining compressed air in the pressure chamber passes through the check valve

Compressed air line into the conveying air chamber and transports any deposits of granules in the conveying line to the end of the conveying line.

In an alternative variant, the compressed air connections are connected to two different compressed air lines. In this variant, two compressed air supplies are provided on the vehicle side, which are transported via two different compressed air lines into the pressure chamber or conveying air chamber. This system is also for a working pressure of 3 bar to 8 bar up to max. Designed for 10 bar, it is suitable for bridging larger conveying paths, for example up to 15 m. If a vent valve is arranged in the compressed air line, the return of the dosing piston to the starting position can be supported.

Fig. 1 shows a schematic diagram of a device mounted on a rail driving device for spreading granules;

2 shows a side section through an embodiment variant of the device according to the invention for spreading granules in a horizontal arrangement;

FIG. 3 shows a sectional view through the device for spreading granules according to FIG. 2 along the section line III - III;

Fig. 4 shows a vertical arrangement of the device for scattering granules in a container for the granules;

5 shows a block diagram to illustrate a method for operating the device for spreading granules according to the invention;

6 shows a block diagram to illustrate an alternative method for operating the device according to the invention for spreading granules; and

7 shows a schematic time diagram for illustration

Control of the compressed air sources for operating the device for spreading granules.

Fig. 1 shows a schematic diagram of a device 1 for spreading granules 2, which is mounted on a rail vehicle 5 mon. The device 1 for spreading granules 2 is connected un ter a container 22 for the granules 2, and doses and conveys a desired amount of granules 2, via a conveyor line 21 in the gap between the wheel 4 of a rail vehicle 5 and 3 rail to increase the friction between rail 3 and wheel 4. The control of the device 1 for scattering the granules 2 is usually carried out manually or automatically.

FIG. 2 shows a side section through an embodiment variant of the device 1 according to the invention for spreading granules 2 in a horizontal arrangement under a container 22 for the granules 2. The device 1 includes a housing 6 with at least one inlet 7 for the granules 2 and at least one outlet 8 for the granules 2, to which a corresponding delivery line 21 is connected, which feeds the metered granules 2 to the desired location. For metering the granules 2 there is an axially movable metering piston 2 within the housing 6. The movement of the metering piston 9 takes place via compressed air, which can be blown with compressed air via a compressed air connection 11 into the pressure chamber 10. If the metering piston 9 is moved away from the initial position, the inlet 7 for the granules 2 is released, whereby a quantity of granules 7 corresponding to the displacement of the metering piston 9 after the axial displacement and duration can be metered in front of the metering piston 9. In the illustrated embodiment, the inlet 7 for the granules 2 is connected to a preferably annular granule chamber 15, so that a uniform, continuous inlet of the granules 2 is possible. Separately from the pressure chamber 10 there is a conveying air chamber 12 within the housing 6 of the device 1, into which conveying air chamber 12 compressed air can also be introduced via a corresponding compressed air connection 13. Via at least one bore 14 in the metering piston 9, the compressed air of the conveying air chamber 12 reaches the end of the metering piston 9 at the outlet 8 for the granulate and thus serves to convey the metered granulate 2 via the delivery line 21 to the desired location, in particular the gap between wheel 4 and rail 3. A plurality of bores 14 are preferably arranged in a ring in the metering piston in order to achieve an annular distribution of the compressed air for conveying the granulate 2. An inclination of the holes 14 with respect to the central axis A of the Dosierkol ben 9, for example by an angle between 1 ° and 5 ° supports a promotion of the granules 2 with the least possible energy consumption. The metering piston 9 can be tapered at the free end, which faces the outlet 8 for the granules 2, which facilitates the metering of the granules 2. The inlet 7 for the granules 2 can also be provided with a certain inclination, preferably 30 ° to 60 °. As a result, a continuous inflow of the granules 2 from a container 22 (not shown) is achieved. A spring 16 is used vorzugswei se for automatically resetting the metering piston 9 in the starting position. The spring 16 can be formed by a helical spring which is arranged in a tight spring chamber 30. about a valve 31, the spring chamber 30 can be vented if necessary. In order to ensure tightness in the starting position of the metering piston 9 and to prevent unwanted leakage of granules 2 from the inlet 7 to the outlet 8, a corresponding seal 20, in particular an O-ring made of a suitable elastic material, can be arranged. To separate the pressure chamber 10 and the conveying air chamber 12, a separating element 17 can be arranged with a corresponding guide for the metering piston 9. The separating element 17, like the element arranged in front of the conveying air chamber 12, is fastened to the housing 6 with corresponding locking screws (not shown), which is indicated by the dash-dotted lines. On the separating element 17 and also on the element arranged in front of the delivery chamber 12, corresponding guides and seals for the axially movable metering piston 9 are also arranged.

In order to prevent a suppression in the inlet 7 for the granules 2, a bypass 18 can be arranged between the conveying air chamber 12 and inlet 7 for the granules 2, via which bypass 18 part of the compressed air used to convey the granules 2 to the inlet 7 of the granules 2 is performed. Via a regulating screw 19 in the bypass 18, the amount of compressed air guided through the bypass 18 can be adjusted.

FIG. 3 shows a sectional view through the device 1 for spreading granules 2 according to FIG. 2 along the section line III-III. In this embodiment variant, the device 1 for spreading granules 2 is arranged essentially horizontally under a container 22 for the granules 2. From the sectional view according to FIG. 3 it can be seen that six bores 14 are arranged annularly in the metering piston 9 in the metering piston 9. The annular granule chamber 15 is also clearly visible in this sectional view. The horizontal arrangement of the device 1 is particularly suitable for retrofitting existing rail vehicles with limited space.

FIG. 4 shows a vertical arrangement of the device 1 for spreading granules 2 in a container 22 for the granules 2. This embodiment variant, which takes up more overall height than a horizontal arrangement, is the device 1 for scattering the granules 2 is arranged in the container 22 for the granules 2. Otherwise, the function of the device 1 does not differ from that of the horizontal arrangement according to FIGS. 2 and 3.

Fig. 5 shows a block diagram to illustrate a method for operating the device 1 according to the invention for spreading granules 2. In this so-called introduction system, a compressed air source 27 is connected via a common compressed air line to both the pressure chamber 10 or its compressed air connection 11 and with the conveying air chamber 12 or its compressed air connection 13. Via a compressed air regulator 28 and a throttle valve 23, the desired level of compressed air for the

Movement of the metering piston 9 on the one hand and the conveyance of the granulate on the other hand can be set. A check valve 26 in the compressed air line 24 serves to ensure that the so-called after blow effect occurs, in which after the end of the metering and conveying method, the compressed air present in the pressure chamber 10 does not expand into the pressure line 24, but rather enters the conveying air chamber 12 and the remaining granules 2 transported away in the För derleitung 21.

In Fig. 6 is a block diagram showing an alternative method for operating the device 1 according to the invention for scattering granules 2 is shown. In the al alternative method, two compressed air lines 24, 25 are connected to the compressed air connections 11 for the pressure chamber 10 and 13 for the conveying air chamber 12, respectively. About appropriate Druckluftreg ler and a corresponding throttle valve 23, the desired levels for the movement of the metering piston 9 and the conveyance of the granules 2 of the compressed air can be set. In this so-called two-line system, the supply of the metering chamber 10 and the supply of the conveying air chamber 12 take place via separate compressed air lines 24, 25 and the function of the metering and delivery can be controlled and regulated independently of one another.

Finally, FIG. 7 shows a schematic time diagram to illustrate the regulation of the compressed air sources for operating the device 1 for spreading granules 2. The compressed air pl the movement of the metering piston is controlled according to the desired metering of the granulate 2. After switching off the compressed air pl for the movement of the metering piston 9, the pressure pl in the pressure chamber 10 slowly drops. The compressed air p2 for the promotion of the granules is about the _Z cutoff eitpunkt the Do sierkolbens 9 also longer enabled a secure transportation of the granules 2 animals through the feed pipe 21 and a corresponding blowing the conveyor line 21 to achieve.

The present device 1 for spreading granules 2 is characterized by fewer components, a space-saving design, a lower weight and lower costs, which means that a wide application is also possible for retrofitting existing rail vehicles. In addition, the objective scattering device is characterized by short reaction times, low wear and low energy consumption.

Claims

Claims:

1. Device (1) for spreading granulate (2), in particular for spreading sand into the gap between rail (3) and wheel (4) of a rail vehicle (5), with a housing (6), at least one inlet ( 7) for the granulate (2) and at least one outlet (8) for the granulate (2), an axially movable dosing piston (9) and a compressed air connection (11) opening into a pressure chamber (10) for actuating the dosing piston ( 9) by means of compressed air for metering the granulate (2), at least one bore (14) being provided in the metering piston (9), characterized in that a conveying air chamber (12) separate from the pressure chamber (10) with a compressed air connection (13 ) is provided, and that the at least one bore (14) in the metering piston (9) the conveying air chamber (12) with the at least one outlet

(8) for the granulate (2) connects, so that the granulate (2) can be conveyed to the at least one outlet (8) by means of compressed air regardless of the dosage.

2. Device (1) according to claim 1, characterized in that in the metering piston (9) a plurality of preferably annular holes (14) are arranged.

3. Device (1) according to claim 2, characterized in that the bores (14) to the central axis (A) of the metering piston (9) are arranged inclined ge.

4. Device (1) according to one of claims 1 to 3, characterized in that around that end of the metering piston (9) which faces the at least one outlet (8) for the granules (2), one with the at least one Inlet (7) for the granulate (2) connected preferably annular granule chamber (15) is angeord net.

5. The device (1) according to any one of claims 1 to 4, characterized in that the at least one inlet (7) for the Granu lat (2) inclined, preferably inclined by 30 ° to 60 °,

in particular is arranged inclined at 45 °.

6. Device (1) according to one of claims 1 to 5, characterized indicates that the end of the metering piston (9), which faces the at least one outlet (8) for the granulate (2), is pointed.

7. Device (1) according to one of claims 1 to 6, characterized in that a spring (16) for resetting the metering piston (9) is provided.

8. The device (1) according to claim 7, characterized in that the spring (16) is arranged in a tight spring chamber (30).

9. The device (1) according to claim 8, characterized in that a valve (31) is arranged in the spring chamber (30).

10. The device (1) according to one of claims 1 to 9, characterized in that the separation between the pressure chamber (10) and the conveying air chamber (12) is formed by a separating element (17) with a guide for the metering piston (9).

11. The device (1) according to any one of claims 1 to 10, characterized in that between the conveying air chamber (12) and the at least one inlet (7) for the granules (2), a bypass (18) for guiding a part of the conveying of the granules (2) used compressed air to the inlet (7) of the granules (2) is arranged.

12. The device (1) according to claim 11, characterized in that a regulating screw (19) is provided in the bypass (18).

13. The device (1) according to any one of claims 1 to 12, characterized in that a seal (20), preferably an O-ring, is arranged between the metering piston (9) and the housing (6).

14. The device (1) according to any one of claims 1 to 13, characterized in that the at least one outlet (8) for the granulate (2) is connected to a delivery line (21).

15. The device (1) according to any one of claims 1 to 14, characterized in that the metering piston (9) is arranged essentially horizontally and the housing (6) from below to a loading container (22) for the granules (2) can be connected.

16. The device (1) according to one of claims 1 to 15, characterized in that the metering piston (9) is arranged substantially vertically and the housing (6) is arranged in a container (22) for the granules (2).

17. The device (1) according to any one of claims 1 to 16, characterized in that the compressed air connections (11, 13) with the interposition of a throttle valve (23) are connected to a common compressed air line (24).

18. The device (1) according to claim 17, characterized in that a check valve (26) is arranged in the compressed air line (24).

19. Device (1) according to one of claims 1 to 16, characterized in that the compressed air connections (11, 13) are connected to two different compressed air lines (24, 25).

20. The device (1) according to claim 19, characterized in that a vent valve (29) is arranged in the compressed air line (24).